I am 30 weeks pregnant I was wondering when does the baby start to turn to be head down position I just saw the dr. Last week and at this moment breec?

Varies. At least 1 out of 3 babies are breech even up to 33 or 34 weeks. About 95% of those will turn spontaneously to the vertex (head down) position before labor occurs.
After 35 weeks. Usually infants are engaged after 35 weeks. However, we don't try and reposition breech babies until 37 weeks. You should know if your baby is breech no later that this. Options then include ecv (external cephalic version) or c-section if the baby stays breech. Ask your doc about breech-tilt maneuvers if you want to try position changes that might help. Good luck.